1.The S3pro headset fits the Meta quest 3/3s series of VR glasses. 2.The S3pro has an adjustable fan that cools the machine and keeps it safe. 3.The B100 battery has a 10,000mAh battery capacity, allowing for extended usage time 4.The BD3 Battery Dock can charge up to 3 B100 batteries at the same time and has a display to show percentages.